Michael Brown's death at the hands of Ferguson police is an all too familiar scenario for Bay Area residents. Oakland and San Francisco lost two of their own, Oscar Grant and Alex Nieto[2], at the hands of local police.

But as hundreds of peaceful demonstrators in Oakland's Frank Ogawa Plaza took part in the National Moment of Silence in honor of Brown, that quiet was disrupted by the loud chop-chop-chop of a helicopter hovering directly overhead.

"Helicopter circling #Oakland #NMOS14 apparently didn't get the memo this will be a silent vigil," tweeted Sigrid Hafstrom, an Oakland resident. Many tweeted and spoke about the disrespect of the hovering chopper.

Some reports are now identifying that helicopter as a California Highway Patrol aircraft, which begs the question: Did state cops buzz over a memorial for those who died at the hand of police?

"I took a look at @flightradar24," Brian McGuigan tweeted to the Guardian, referencing a flight radar web and phone application[3], "Seems there was a helicopter with the call-sign 'CHP32' in the area around then."

Taking that CHP to mean the California Highway Patrol, we at the Bay Guardian took it upon ourselves to call that state law enforcement agency to identify the helicopter. Officer W. Ogilvie, an on-call spokesperson, confirmed CHP32 is a radar tag used by the CHP, but wouldn't offer any details beyond that.

"That is a call sign we use," he told us. "It is possible that was a call sign [for a helicopter] for that area." When we asked if he could confirm that a CHP helicopter hovered over Frank Ogawa Plaza at 4pm, he told us the CHP does not inform the public of vehicle movements.

McGuigan, an aviation enthusiast, tweeted us a photo of the aviation radar allegedly depicting the helicopter. The flight path shows an aircraft with the tag CHP32 flying just around Frank Ogawa Plaza at about 3pm. Closer to 4:15pm the radar tag "CHP32" dropped, but the radar showed the now unidentified aircraft hanging over Frank Ogawa Plaza at exactly the time a helicopter buzzed over the demonstrators' moment of silence.

McGuigan said radar tags often drop when aircraft enter crowded flight areas. The Federal Aviation Administration confirmed this to the Guardian, telling us radar tags often drop when aircraft enter busy airspace or they "hover too low."

"Hard to say for sure," McGuigan said, about whether they were the same craft, "but CHP32 was last tagged right where the guy ended up orbiting."

One reporter on the ground, Julia Carrie Wong, said Oakland Police told her the chopper belonged to a news station. When we asked the FAA to confirm with us the radar tags used by news stations and the CHP at the time of the helicopter sighting, the agency told us we'd need to file a Freedom of Information Act request. But protesters the Guardian spoke to described the helicopter's color scheme as white with a blue tail, the same color scheme as CHP aircraft.

Just a bit of advice for the CHP and other law enforcement agencies: Next time people peacefully protest police violence and the militarization of local cops, you may not want to prove their point by hovering helicopters directly over even the most benign of demonstrations.

You can watch the peaceful demonstration and hear the chopper for yourself, below.